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Matadi is the chief sea port of the Democratic Republic of the Congo and the capital of the Kongo Central province, adjacent to the border with Angola. It had a population of 245,862 (2004). Matadi is situated on the left bank of the Congo River, 148 km (92 mi) from the mouth and 8 km (5.0 mi) below the last navigable point before the rapids that make the river impassable for a long stretch upriver.